About Sacred Vessels and other altar appointments
There are a lot of different terms for the items you find on a Catholic altar. Here is a brief glossary of altar terms.
A small bell, originally kept at the epistle side of the altar, rung at the Sanctus and Elevation during Mass as an invitation to those present to alert them to the solemnity of the Eucharistic consecration. In some countries, the bell was also rung first before the Consecration, and before the Communion of priest and the faithful. Although no longer prescribed by the rubrics, it is a laudable and approved practice to ring the altar bell at least at the Elevation of the Host and the chalice.
Special cloths cover the altar and are often left on the altar when it is not in use. According to the rubrics of the Church, the only materials acceptable for use as an altar cloth are linen made from flax or hemp. The cloths historically used by the Church are (working from the table of the altar itself up through the layers) :
The cere cloth was originally a piece of heavy linen treated with wax (cere is the Latin word for "wax") to protect the other linens from the dampness of a stone altar, and also to prevent the altar from being stained by any wine that may be spilled. It is the exact same size as the 'mensa', or the flat rectangular top of the altar.
The linen cloth is, like the cere cloth, made of heavy linen exactly the same size as the mensa of the altar. It acts as a cushion and, with the cere cloth, prevents the altar from being dented by heavy vases or communion vessels placed on top. Two of these cloths are traditionally placed over the cere cloth and thus under the fair linen.
The fair linen is the long, white linen cloth laid over the linen cloth. Like the two cloths laid before it, it is the same depth as the mensa of the altar, but is longer, so it hangs over the edges to within a few inches of the floor. Some authorities say it should hang eighteen inches over the edge of the ends of the mensa. It is usually trimmed with lace on the ends, and should be hemmed by hand, with a one or two inch hem on all sides. Five small crosses are embroidered on the fair linen - one to fall at each corner of the mensa, and one in the middle of the front edge. These symbolize the five wounds of Jesus. The fair linen should be left on the altar at all times. When it is removed for replacement it should be rolled and not folded. It symbolizes the shroud in which Jesus was wrapped for burial.
The coverlet is of the same heavy linen as the cere cloth and the linen cloth, the same length and width as the fair linen, and is left on the altar whenever it is not in use. It simply protects the altar from dust and debris.
All of the linen altar cloths are white, including their decoration. Other more decorative cloths are used to decorate the front and back of the altar such as:
The frontal, or Antepedium, is the same size as the front of the altar. It is richly decorated, made of tapestry, silk or damask. Some frontals are matchless works of art, exhibiting the finest materials and embroidery possible. Other churches opt for a plain frontal. One characteristic is shared by all frontals: they are colored green, red, violet, black or white, and are changed according to the color of the Church year. In this way the altar will have five different frontals hung upon it throughout the year, but only one at a time. The frontal may be fixed to either the cere cloth or the linen cloth to hold it in place, which cloth must be fastened to the rear edge of the altar.
The frontlet is similar to the frontal, that is the exact width of the altar, but only ten to twelve inches deep. It hangs over the frontal, and is of the same color and material. Again, the frontlet is rotated according to the color of the church year. Like the frontal the frontlet is fastened to either the cere cloth or the linen cloth. Or, alternatively, it may be fastened to a wooden frame or strip that can be hooked in place at the front of the altar.
A box in which the holy oils are kept in Catholic Churches. It is either affixed to the wall or inserted in the wall of the sanctuary. (From the Latin armarium, a chest or safe.)
A stiff pocket about twelve inches square in which the folded corporal is carried to and from the altar. Part of a set of vestments, it is made of matching material. It is placed upon the chalice at the beginning and end of Mass and on the altar at Benediction. The leather case containing the pyx, in which the Holy Eucharist is brought to the sick, is called a burse. It is also the name for an endowment or foundation fund especially for scholarships for candidates for the priesthood. (From the Latin bursa, purse or pouch.)
The cup-shaped vessel or goblet used at Mass to contain the Precious Blood of Christ. For centuries it was made of precious material; if it was not of gold, the interior of the cup was gold-plated. Since the Second Vatican Council, chalices may be of other materials. A chalice is consecrated with holy chrism by a bishop. Re-gilding the inside does not destroy the consecration. sometimes the word chalice designates its contents. (From the Latin calix, cup, goblet, drinking vessel, chalice.)
A covering for the chalice used at Mass. According to the Church's prescription, since the Second Vatican Council "the chalice should be covered with a veil, which can always be white in color" (Eucharistiae Sacramentum IV, 80). In the Tridentine Rite, the chalice veil matching the vestment liturgical colors.
A covered container used to hold the consecrated small Hosts. It is similar to a chalice but covered and larger, used for small Communion hosts of the faithful. It is made of various precious metals, and the interior is commonly gold or gold-plated. Also synonymous with baldachino as the dome-shaped permanent canopy over a high altar, supported by columns and shaped like an inverted cup. (From the Latin ciborium; from Greek kib_rion, cup.)
A square white linen cloth on which the Host and Chalice are placed during Mass. When not in use it may be kept in a burse. It is also used under the monstrance at Benediction or under the Blessed Sacrament at any time. (From the Latin corporalis, bodily; from corpus, body.)
One of two small bottles or vessels to contain the water and wine used at the Consecration of the Mass. They are presented as offerings of the faithful at the Offertory. The cruets are also used for a priest's ablution after the Offertory, and the ablution of the chalice after Holy Communion.
A monstrance, a metal vessel usually gold- or silver-plated with a transparent section in which the Sacred Host is placed in its lunette when exposed for adoration or carried in procession. It varies in shape and ornamentation, popular models being tower-shaped or round; a metal circlet surrounded with rays or bars resting on a stem rising from a heavy base, many ornamented with jewels. The ostensorium in the Cathedral of Toledo took more than a hundred years to make and is reputed to be of gold brought by Columbus from America.
A sacred covering. Most commonly, a pall is the stiff square cardboard covered with lined, spread over the top of the chalice at Mass; also a clothe covering, ornamented or plain, placed over the coffin at funeral Masses and over the catafalque at later requiem Masses for the dead; a veil partially covering the bride and groom in marriages of the Mozarabic rite; and a veil placed over the nun at profession ceremonies to some contemplative enclosed orders. (Etym. Latin pallium, cloak.)
A saucer-like dish of the same material as the chalice--gold-plated and consecrated by a bishop or his delegate with holy chrism. It must be large enough to cover the chalice. On it rests the bread to be consecrated, and later on the Sacred Host. it was customary to have a subdeacon hold the paten, covered by the humeral veil, from the Offertory to the Pater Noster in solemn Masses. (From the Latin patena, a broad, shallow dish or pan.)
A small piece of white linen, marked with a cross in the center, used by the priest in the celebration of Mass. It is folded in three layers and used by the priest to purify his fingers and the chalice and paten after Holy Communion.
Any metal box or vessel in which the Blessed Sacrament is kept or carried. The term is more aptly applied to the small round metal case (usually gold-plated) used by a priest to carry a few hosts on his visitation to the sick. but the larger ciborium is also called a pyx. (From the Greek puxis, box.)
The censer or vessel in which incense is burned at liturgical services. It consists of a cup-shaped metal body for holding charcoal and incense, with a separate lid for controlling the smoke and fire, and a chain, or chains, allowing the censer to swing safely without spilling its contents. (From the Latin t[h]uribulum, from t[h]us, [stem t(h)ur-], incense; from Greek thuos [sacrificial] incense, burned offering, offering.)